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| Commercial timbers |
Nomenclature etc. BORAGINACEAE. Syn. Patagonula americana L. Trade and local names: guajayvi (PY, AR);guaiuvira, guaiabira, guajivira, guarapuvira, guajuvira, guaraiúva, guajuvira-branca (BR). Not protected under CITES regulations.
Tree. Geographic distribution: southern Brazil, temperate South America.
General. Growth ring boundaries distinct (demarcated by fine marginal parenchyma bands and slightly thickened (noded) rays). Heartwood basically brown; with streaks. Sapwood colour distinct from heartwood colour. Density 0.7–0.8 g/cm³.
Vessels. Vessels present. Wood diffuse porous (with a tendency towards semi-ringporous). Vessels arranged in tangential bands, in multiples, commonly in short (2–3 vessels) radial rows and in clusters. Average tangential vessel diameter 70 µm. Average number of vessels/mm² 30–55. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 4–6 µm, pits vestured. Vessel-ray pits with distinct borders, similar to intervessel pits. Tyloses present, thinwalled. Other deposits present, light and dark brown organic contens.
Tracheids and fibres. Fibres of medium wall thickness. Fibre pits mainly restricted to radial walls, simple to minutely bordered.
Axial parenchyma. Axial parenchyma present, banded. Bands marginal (or seemingly marginal). Bands fine. Axial parenchyma apotracheal and paratracheal. Apotracheal axial parenchyma diffuse-in-aggregates. Paratracheal axial parenchyma vasicentric and confluent. Axial parenchyma fusiform (few), or as strands. Average number of cells per strand: 2–4(–5).
Rays. Rays 4–7 per tangential mm, multiseriate, (2–)3–5 cells wide. Height of large rays commonly 500 to 1000 µm. Rays composed of two or more cell types (heterocellular). Heterocellular rays with square and upright cells restricted to marginal rows, mostly 1 marginal row of upright or square cells and mostly 2–4 marginal rows of upright or square cells. Sheath cells present.
Mineral inclusions. Crystals present, in form of crystal sand, located in ray cells, axial parenchyma cells, and fibres. Crystal-containing ray cells upright and/or square and procumbent. Crystal sand very frequent in marginal ray cells and sheath cells. Silica not observed.
Illustrations. • Transverse section. • Tangential section. • Radial section. • Crystals. microcrystals (crystal sand) in rays: procumbent, upright and sheath cells.
The interactive key allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting specified attributes, summaries of attributes within groups of taxa, and geographical distribution.
Cite this publication as: ‘Richter, H.G., and Dallwitz, M.J. 2000 onwards. Commercial timbers: descriptions, illustrations, identification, and information retrieval. In English, French, German, Portuguese, and Spanish. Version: 9th April 2019. delta-intkey.com’.
